Redundant inspection

ABSTRACT

The invention relates to an inspection device ( 1 ) for checking bottles ( 2 ) or similar containers, comprising at least one first camera ( 9, 11, 12, 13 ), which checks a defined region of the bottle ( 2 ) or similar container. The at least one camera ( 9, 11, 12, 13 ) is arranged on an optic channel ( 6 ), on which at least one second camera ( 9, 11, 12, 13 ) is arranged, which checks the same defined region as at least the first camera ( 9,11,12,13 ). A third and fourth camera ( 9, 11, 12, 13 ) is arranged on the optical channel ( 6 ), which together check a further, defined region.

The invention relates to an inspection device for checking bottles or similar containers, said inspection device comprising at least one first camera, which checks a defined region of the bottle or of the similar container.

These types of bottles or these types of containers can be used for liquids, for example for beverages. The containers can be produced from a transparent or translucent material, for example glass, or from a translucent plastics material, e.g. PET. The bottles or similar containers are moved passed the inspection device in the empty state, preferably after having been cleaned. To this end, an illuminating device is located, for example, below the bottle in question, the at least first camera being located opposite said illuminating device. The illuminating device illuminates the bottle in question such that the at least one camera can check whether there are, for instance, any foreign substances such as, for example, adhesive films (TESA®) or other unwanted objects, contaminants or damage in or on the bottle.

To this end, the at least first camera is aligned onto a bottom region of the bottle in question such that only the bottom region or the bottle bottom is inspected from the inside. By means of a second inspection device it is possible to inspect an inside wall region of the bottle in question for unwanted objects, contaminants or damage. If the two inspection devices detect that there are unwanted objects in the bottle, or that the bottle has contaminants or damage in or on the inspected region, the relevant bottle is rejected. Corresponding means are provided for this purpose, carrying out an image comparison or image processing of the image taken by the camera, and transmitting a corresponding signal to suitable sorting devices. Inspecting the interior of the bottle in question for liquid residue or the like is also known, it being possible to provide a camera that processes infrared light for this purpose. The inspection devices inspect the relevant region (bottom and/or inside wall) but only once each time. This means that errors can occur in this case so that, potentially, only unreliable assertions regarding the inspected region can be made with regard to unwanted objects, contaminants and/or damage. In addition, the use of a plurality of inspection devices following one after the other is disadvantageous as the respective bottle or similar container has to run through a plurality of inspection devices in order to be able to inspect the defined inside regions.

Consequently, it is the object of the invention to inspect bottles or similar containers in a cost-effective manner, an inspection device of the aforementioned type being improved by simple means such that it is possible to check the defined region of the bottle or of the container to be inspected in a reliable manner.

This object is achieved according to the invention by an inspection device with the features of claim 1, wherein the at least one camera is located at an optical channel which has at least one second camera, said second camera inspecting the same region as the at least first camera, and wherein at the optical channel there is located at least one third and fourth camera, which together inspect a further inside region of the bottle or of the similar container.

The invention advantageously makes available a single inspection device which checks the defined region to be inspected in each case at least twice for unwanted objects and contaminants in the interior of the bottle or of the similar container and/or for damage, by a second additional camera inspecting the region inspected by the first camera. In other words, both cameras, that is the at least first camera and the additional second camera, are set to one and the same region, that is to the defined region to be inspected, such that, at the same time, the respective camera checks the region to be inspected independently of the respective other camera. This means that two images of the defined region to be inspected can be taken and processed, which means that the reliability of the assertions made, for example with regard to the presence of unwanted objects in the interior of the bottle or of the similar container and/or with regard to damage, is increased in a considerable manner with reference to a one-off inspection.

As the two cameras are also located in an expedient manner on the optical channel, another very complicated inspection device is provided in a favourable manner. More details of the development of the optical channel can be found below.

The two cameras can be located, when viewed in a longitudinal direction of the optical channel, one above the other and to the side of the optical channel. It is also conceivable for the two cameras to be located opposite one another, with reference to a central axis of the optical channel.

The bottom of the bottle in question, for example, can be inspected in a reliable manner by using the two cameras. In a preferred development of the invention, two further cameras, that is the third and fourth cameras, are located at the optical channel and said third and fourth cameras inspect another defined region of the bottle in question, for example its side wall. It is also possible for said two cameras to be located to the side of the optical channel and, when viewed in its longitudinal direction, one above the other.

In this case any expedient sequence of four cameras is conceivable, for example when viewed in the longitudinal direction, the bottom two cameras located opposite one another at the side inspect the bottom and the other two inspect the side wall of the bottle in question.

In a further preferred development, it is also possible to locate a camera that processes infrared light at the optical channel, said camera being able to detect liquid residue, for example, in the interior of the bottle in question in a reliable manner.

In order to be able to realize the possible arrangements of five cameras in each case in the preferred manner, it is provided in an expedient development that, when viewed in longitudinal section, the optical channel is preferably rectangular and has optical elements. Naturally it is also possible to select any other suitable geometric arrangement for the optical channel. The optical elements can be realized as so-called beam splitters and optical lenses.

At its inspection end oriented towards the bottle in question, the optical channel preferably has two optical lenses that are located one above the other when viewed in the longitudinal direction. This means that it is possible to inspect both the bottom (two cameras) and the side wall (two cameras) of the bottle in question using the single inspection device according to the invention.

The beam splitters are located in the interior of the optical channel, each camera that is located to the side having associated therewith in each case one beam splitter. Beam splitters in terms of the invention are partially transparent optical elements, which partially allow through and partially reflect (light) beams. In a preferred development, when viewed in the longitudinal direction, the beam splitters are accordingly arranged one above another, this favourable manner having different transparency values and reflection values so that even the last camera, when viewed in the longitudinal direction, is still able to inspect the interior of the bottle in question in a reliable manner. For example, when viewed in the longitudinal direction from the inspection end, the first beam splitter has a smaller reflection value and a high transparency value (e.g.: 30/70), wherein, when viewed in the longitudinal direction with reference to the inspection end, the last beam splitter has a higher reflection value with reference to the first beam splitter and a smaller transparency value (e.g.: 60/40). The transparency values and reflection values of the beam splitters located in between are adapted accordingly. In this respect the beam splitters can also be identified as transparent mirrors. The beam splitters are realized such that infrared light is not reflected, that means they are completely transparent to infrared light.

In an expedient manner, as already described, each laterally arranged camera has associated therewith a beam splitter, which in each case reflects beams in the direction of the respective correlated camera, such that the relevant inside region of the bottle in question (bottom/side wall) can be photographed in each case by the corresponding camera. Another favourable factor in terms of the invention is when at least each of the laterally arranged cameras has associated therewith another optical lens in addition, such that the respective camera can be adapted to the corresponding optical length, or such that the optical ratio can be set for the corresponding camera by means of the lens. The lens associated with the cameras can be accommodated in a housing (close up), which can be located between the respective cameras and the side wall of the optical channel.

All in all, the invention makes available a single inspection device, which, with a complicated design, enables reliable checking of defined regions of the bottle in question by, on the one hand, photographing the inside bottom and, on the other hand, the inside side wall of the bottle in question in each case twice, but only one single inspection device being necessary. In an advantageous manner, the bottle or similar container does not have to be set in rotation in this case as the optical channel with its optical elements enables a complete image in the radial direction of the respective region. Another advantage is that it is possible to operate the two cameras, which in each case inspect the same inside region (bottom/side wall), at different polarizations so that one can be operated in bright field and the other in dark field. Films are easier to recognize by means of dark field inspection. Naturally, it is within the terms of the invention to arrange even more than the mentioned five cameras at the optical channel such that more regions than the inside regions described can be inspected.

Further advantageous developments of the invention are disclosed in the sub claims and the following description of the Figures, in which, in detail:

FIG. 1 shows an inspection device according to the invention with cameras located at an optical channel.

FIG. 1 shows an inspection device 1 for checking bottles 2 or similar containers. Bottles 2 or similar containers are referred to below in a general manner as bottle 2.

The bottle 2 has a bottom 3 and a side wall 4. A mouth opening is located opposite the bottom 2. Using the inspection device 1, preferably the interior of the bottle is checked, preferably after having been cleaned, for unwanted objects, contaminants and/or damage. In this respect, this can be called an empty bottle inspection.

The inspection device 1 includes an illuminating device (not represented). In the exemplary embodiment in question, the illuminating device is located below the bottle 2, which is conveyed past the illuminating device, for example, in a suspended manner. The illuminating device shines through the bottle 2 from below.

In the exemplary embodiment represented, the inspection device 1 has an optical channel 6. When viewed in longitudinal section, the optical channel 6 is rectangular with an inspection end 7 and a head end 8 located opposite said inspection end.

Four cameras 9, 11, 12, 13 are each located to the side of the optical channel 6. A fifth camera 14 is located at the head end 8. The cameras 9 and 12 as well as 11 and 13, when viewed in the longitudinal direction of the optical channel 6, are located one above the other. With reference to the central axis X of the optical channel 6, two cameras 9 and 12 are located on the right-hand side in the drawing plane and the two other cameras 11 and 13 are located on the left-hand side of the optical channel 6 in the drawing plane.

In each case, two of the four cameras 9 to 13 located to the side together check defined inside regions of the bottle 2. For example, the cameras 9 and 12 check the bottom region and the cameras 11 and 13 check the side walls. Consequently, two photographs of the respective defined region to be inspected are taken by one single inspection device 1.

Naturally, the named sequence of the cameras 9 to 13 is purely to be understood as an example. Thus it is possible, within the terms of the invention, for the cameras 9 and 11 or 9 and 13 to inspect the bottom region or the side wall and the cameras 12 and 13 or 11 and 12 to inspect the respective other region.

The fifth camera 14 located at the head end checks whether there is any unwanted liquid residue in the bottle 2.

In order to be able to supply the respective cameras 9 to 14 with the desired information, optical elements are located in the optical channel 6, said optical elements being realized as beam splitters 16 or optical lenses 17. In this respect, the optical channel 6 can also be described as an optical tower, on which the five cameras 9 to 14 and the optical elements 16 and 17 are located.

In the exemplified embodiment represented, two lenses 17, located one above the other in the longitudinal direction, are located at the inspection end 7. At least each of the cameras 9 to 13 located at the side has associated therewith in each case a further lens (not represented) and these are each accommodated in a housing 18. The housing 18 is located between a side wall 19 of the optical channel 6 and the respective camera 9 to 13.

In addition, each of the cameras 9 to 13 located to the side has associated therewith a beam splitter 16. The beam splitters 16 are realized such that even the last camera when viewed in the longitudinal direction can be supplied with information. This means that the beam splitters 16 following one after the other in the longitudinal direction preferably have different transparency or reflection values in each case.

Corresponding openings in the side wall 19 or in the head end 8 are naturally provided in the region of the cameras 9 to 14.

By means of the single inspection device 1 according to the invention, a reliable inspection of the interior of the bottle 2 can be carried out advantageously in this manner. To this end, in each case two cameras are provided which, in each case, inspect the same defined region of the bottle 2. Two further cameras check another defined inside region of the bottle 2. In this respect a very complicated inspection device 1, is made available, by way of which different inspection regions of the bottle can be checked, in a reliable manner. The optical channel 6, in this case, is provided in a favourable manner with optical elements such that, in each case, the correlating cameras can be supplied with the corresponding information.

LIST OF REFERENCES

-   -   1 Inspection device     -   2 Bottle     -   3 Bottom     -   4 Side wall of 2     -   5     -   6 Optical channel     -   7 Inspection end     -   8 Head end     -   9 Camera     -   10     -   11 Camera     -   12 Camera     -   13 Camera     -   14 Camera     -   15     -   16 Beam splitter     -   17 Optical lens     -   18 Housing     -   19 Side wall of 6 

1. An inspection device for checking containers, said inspection device comprising: at least one first camera that checks a defined region of the container, the at least one camera being located at an optical channel, at which is also located at least one second camera, said second camera inspecting the same defined region as the at least first camera, and, at least one third and fourth camera, which together inspect a further defined region of said container.
 2. The inspection device according to claim 1, wherein the at least two cameras that inspect the same defined region are located, when viewed in a longitudinal direction of the optical channel, one above the other to the side of the optical channel.
 3. The inspection device according to claim 1, wherein the two cameras that inspect the same defined region are located opposite one another with reference to a central axis of the optical channel.
 4. The inspection device according to claim 1, further comprising a further camera for taking infrared light photographs, said further camera being located at a head end of the optical channel.
 5. The inspection device according to claim 1, wherein the optical channel is rectangular when viewed in longitudinal section, and wherein the optical channel comprises optical elements.
 6. The inspection device according to claim 1, further comprising at least one beam splitter is located in the optical channel.
 7. The inspection device according to claim 1, wherein the optical channel has an inspection end, and wherein the inspection device further comprises at least one optical lens in the optical channel.
 8. The inspection device according to claim 1, further comprising a plurality of optical lenses, each of which is associated with a corresponding camera.
 9. The inspection device according to claim 1, further comprising a plurality of beam splitters, each of which directs a portion of a beam to one of said cameras, each of said plurality of beam splitters being located along the optical channel.
 10. The inspection device according to claim 9, wherein a first beam splitter from the plurality of beam splitters has a first transparency, and a second beam splitter from the plurality of beam splitters has a second transparency, said second transparency being greater than said first transparency.
 11. The inspection device according to claim 1, wherein the optical channel has an inspection end, and wherein the device further comprises at least two optical lenses at the inspection end the optical channel, said optical lenses displaced relative to each other along the longitudinal axis of the optical channel.
 12. The inspection device according to claim 1, wherein the optical channel comprises an optical tower.
 13. The inspection device according to claim 1, wherein said containers are bottles.
 14. An apparatus for inspecting containers, said apparatus comprising: an optical channel; a first camera in optical communication with said optical channel, said first camera being configured to inspect a first defined region of said container; a second camera in optical communication with said optical channel, said second camera being configured to inspect said first defined region; a third camera in optical communication with said optical channel, said third camera being configured to inspect a second defined region of said container; and a fourth camera in optical communication with said optical channel, said fourth camera being configured to inspect said second defined region;
 15. An apparatus for inspecting containers, said apparatus comprising: an optical channel; and in optical communication with said optical channel, means for generating two independent optical inspections of a first defined region of said container, and means for generating two independent optical inspections of a second defined region of said container. 